Playing the traveler instead of the sheet is just a different way of depowering the sail. Playing the traveler is changing the angle of attack of the wing while keeping the twist in the sail (sail shape) relatively the same. I have tried both and found that on my older boats the traveler did not run as smoothly or easily as the main sheet blocks. It may just be preference. Give it a try and see which you like better.

And now can you explain the absurdity of apparent wind directions on a downwind hydrofoil?

That one's easy. On a windy day, drive down a highway that the wind is blowing across. Stick your hand out the window and notice where it feels like the wind is coming from- in front of the car. It's because the car is moving so fast that the "wind" it creates overpowers the actual "true wind" that you would feel if stationary, so it feels like the wind is coming from more or less in front of you. Apparent wind on a boat is exactly the same thing:the hydrofoiling AC72's just go so fast that the boat speed component is huge. This means that the apparent wind is always in front of them, and so it looks like the sails are always trimmed for "upwind". Iceboats have been experiencing this exact same phenomenon for years

Not just Iceboats.Many years ago I attached an universal joint to the front of my long skateboard and then My sailboard sail. I would go in empty parking lots. There was so little drag that on a reach I would gradually bear off and maintain apparent wind until I could travel at double the windspeed.I sometimes had to backwind to slow down before a gybe.

Answered my own question re tweaking the traveler in lieu of the main sheet…

Didn't work for me. Mainly because the traveler has no mechanical advantage. It's so much easier and smoother finessing the sheets using a 6:1 purchase.

Leaving the traveler uncleated in big wind would rip my arm off after awhile, but I have been discovering many other productive uses for the traveler. Especially to avoid or escape becoming stuck in irons.

It's already been mentioned, but I second 'Rick White's Catamaran Racing for the 90's'It's my favorite book on the subject!If you are a day sailor, don't be put off by 'racing for the 90's' in the title, this book is a gem.I guarantee what ever type of sailing you do whether it be day sailing for fun or serious racing you will learn something useful and new

That video was from the 2011 H-16 North Americans on an afternoon that racing had been called off for too much wind so Mark and Ryan went out to play. Mark and Ryan took third at the 2011s and Mark and his daughter, Grace, took 2nd at the 2013 H-16 North Americans.

Anthony Dutchatel and myself with Max.Hudson were the first ones out playing in the gusty offshore breeze.Water was nice and flat close to shore.A friend of Anthony,s took about 500 pics of his boat and mine out match racing.He later gave me a copy of the CD with all the pics.Couple of them turned into nice framed blow ups.

We (the race committee) were sitting about 1.5 miles offshore that day. It was not flat, and it was howling - literally. We were judging the wind speed by the noise of the rigging on the large sailboat that was the signal boat.

Gusts into the high 20's, 49°F air temp, wind chill was in the 30's. The guys on the mark boats had taken shelter on the signal boat because they were wet and cold.

We didn't have enough safety boats to keep people from drifting to Cancun - 600 miles away across the Gulf of Mexico - and that was the primary reason we abandoned racing for the day.

That, and Pedrin texted me a photo of the Venezuelan rum waiting for me when we got in if I called it off

Yes I agree it was the right call by the RC to call for the day.Like I said with an off shore breeze ,it was flat near shore.Having said that we really did have a great sail,ripping up and down the shore line of the Emerald Coast

Really late to the party, BUT, I setup a very interesting traveler situation where I could totally control the traveler both below center for really serious high wind, and above center for dead air. No clue if today the rules allow what I did, BUT I had a setup that would bring the traveler above center and hold it.

In very light wind to dead air I would bring it up about 1/3 to 1/2 of the way above center and release the main. It gave a huge twist to the main and as stated with the other posts developed an incredible amount of torque that got me moving where my competition stayed dead in the water or had nowhere the speed I had in light air.In heavy air, on a reach, I would pull it just a touch above center and let the main out and twist, giving us more power than the others and we would simply walk away.